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The enzymes of the proline utilization pathway (the products of the PUT] and PUT2 genes) in Saccharomyces cerevisiae are coordinately regulated by proline and the PUT3 transcriptional activator. To learn more about the control of this pathway, constitutive mutations in PUT3 as well as in other regulators were sought. A scheme using a gene fusion between PUT) (S. cerevisiae proline oxidase) and galK (Escherichia coli galactokinase) was developed to select directly for constitutive mutations affecting the PUT) promoter. These mutations were secondarily screened for their effects in trans on the promoter of the PUT2 (A'-pyrroline-5-carboxylate dehydrogenase) gene by using a PUT2-lacZ (E. coli j8-galactosidase) gene fusion. Three The proline utilization (Put) pathway of Saccharomyces cerevisiae is a model system for studying transcriptional activation and nuclear localization, amino acid transport, mitochondrial protein import, and compartmentation. Proline oxidase, the first enzyme in the pathway and the product of the PUT] gene, converts proline to A1-pyrroline-5-carboxylate (P5C); its activity requires a functional electron transport chain (10, 12). The second reaction, conversion of P5C to glutamate, is carried out by P5C dehydrogenase, the product of the PUT2 gene (9, 10). Both genes have been cloned and sequenced, and their gene products were localized to mitochondria, where proline catabolism takes place (7,32,54,55). Each enzyme is made as a precursor and is processed to its mature form by cleavage of a presequence during mitochondrial import (31; J. Kaput and M. C. Brandriss, unpublished results).Proline induction of PUT] and PUT2 is mediated by the product of the PUT3 gene. The PUT3 protein was identified as a transcriptional activator of the Put pathway on the basis of analysis of two mutant alleles that affected the expression of proline oxidase and P5C dehydrogenase. The semidominant PUT3c-68 mutation caused inducer-independent expression of the enzymes and increased basal RNA levels (7,11,54); the recessive put3-75 mutation caused enzyme expression to be noninducible by proline (8,49).We were interested in determining whether genes other * Corresponding author.

PurposeIn order to gain an insight into determinants of reported variability in immune responses to respiratory viruses in human bronchial epithelial cells (HBECs) from asthmatics, the responses of HBEC to viral infections were evaluated in HBECs from phenotypically heterogeneous groups of asthmatics and in healthy controls.MethodsHBECs were obtained during bronchoscopy from 10 patients with asthma (6 atopic and 4 non-atopic) and from healthy controls (n=9) and grown as undifferentiated cultures. HBECs were infected with parainfluenza virus (PIV)-3 (MOI 0.1) and rhinovirus (RV)-1B (MOI 0.1), or treated with medium alone. The cell supernatants were harvested at 8, 24, and 48 hours. IFN-α, CXCL10 (IP-10), and RANTES (CCL5) were analyzed by using Cytometric Bead Array (CBA), and interferon (IFN)-β and IFN-λ1 by ELISA. Gene expression of IFNs, chemokines, and IFN-regulatory factors (IRF-3 and IRF-7) was determined by using quantitative PCR.ResultsPIV3 and RV1B infections increased IFN-λ1 mRNA expression in HBECs from asthmatics and healthy controls to a similar extent, and virus-induced IFN-λ1 expression correlated positively with IRF-7 expression. Following PIV3 infection, IP-10 protein release and mRNA expression were significantly higher in asthmatics compared to healthy controls (median 36.03-fold). No differences in the release or expression of RANTES, IFN-λ1 protein and mRNA, or IFN-α and IFN-β mRNA between asthmatics and healthy controls were observed. However, when asthmatics were divided according to their atopic status, HBECs from atopic asthmatics (n=6) generated significantly more IFN-λ1 protein and demonstrated higher IFN-α, IFN-β, and IRF-7 mRNA expressions in response to PIV3 compared to non-atopic asthmatics (n=4) and healthy controls (n=9). In response to RV1B infection, IFN-β mRNA expression was lower (12.39-fold at 24 hours and 19.37-fold at 48 hours) in non-atopic asthmatics compared to atopic asthmatics.ConclusionsThe immune response of HBECs to virus infections may not be deficient in asthmatics, but seems to be modified by atopic status.

Background8-Isoprostane (8-IP) is a marker of lipid peroxidation. Elevated concentrations have been reported in BAL fluid and exhaled breath condensate (EBC) in sarcoidosis (S). To validate the prognostic value of this marker we tested whether: 1. high initial EBC 8-IP predispose to more severe disease; 2. low initial concentrations increase a chance of early remission; 3. remissions are connected with the decrease of EBC 8-IP.Methods40 patients (S) have been examined initially (V1) and after 8.5 ± 0.5 months (V2). EBC 8-IP concentrations were measured by ELISA. Chest X-ray, lung function test, serum ACE and Ca2+ concentrations, 24 hrs Ca2+loss, abdominal ultrasonography, symptoms evaluation were performed.ResultsWe confirmed higher concentrations of 8-IP in EBC of patients with sarcoidosis (p = 0.001). Relative risk (RR) of persistence of disease at V2 when initial 8-IP was above 20 pg/mL was 1.04, and the frequency distributions estimated by χ2 test were not significantly different. A chance (RR) of early complete remission when V1 8-IP was below DL, was 3.33 (p = 0.04 by χ2 test). A significant decrease of 8-IP at V2 was observed only in patients who received treatment (p = 0.03), but not in those with spontaneous remission.ConclusionsWe come to the conclusion, that low initial 8-IP may be a positive prognostic factor. A decrease of 8-IP in treated patients reflects a non-specific effect of treatment and is not related to mere regression of disease.

Abstract. Exhaled breath condensate (EBC) has been increasingly used as a new and non-invasive method to study airway inflammation. In this study we have compared the concentrations of lipid mediators in EBC with concentrations in bronchoalveolar lavage fluid (BALF). We included 37 patients undergoing bronchoscopy (12 sarcoidosis, 12 COPD, 6 lung cancer, 5 chronic cough, 1 Wegener's granulomatosis, 1 sclerodermia). Patients were not allowed to have exacerbation or any change in concomitant medication for at least 4 weeks prior to the study. In all patients, EBC was collected immediately prior to the bronchoscopy. The levels of cys-LTs, LTB4, 8-isoprostane were significantly higher in BALF compared to EBC (p < 0.0001, p < 0.001, p < 0.0001 for cys-LTs, LTB4, 8-isoprostane respectively). Moreover, there was a strong positive correlation between both leukotriene B4 and 8-isoprostane in BALF and EBC (r = 0.53 and r = 0.79, p < 0.01, respectively) in patients with sarcoidosis and COPD but there was no correlation between eicosanoids BALF and EBC in patients with chronic cough and lung cancer. This is the first study to compare EBC and BALF in different lung diseases which demonstrated significant correlations between the levels of eicosanoids in BALF and EBC in patients with COPD and sarcoidosis. EBC may be useful in measuring inflammation in several inflammatory lung diseases.